As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT 18,000 FEET, PILOT SMELLED SMOKE. CABIN TEMP WENT FULL HOT. SHUT DOWN ENVIRONMENTAL CONTROL UNIT. WHEN ON GROUND, TROUBLESHOOTING FOUND THE CARBON FACE SEAL OF THE AIR CYCLE MACHINE HAD FAILED ON THE OUTPUT SIDE ALLOWING OIL INTO THE CABIN AIR.